#1 没有保证一个人只收一份礼物
import random
name_list=["zhouyuqing","xiajingwei","youshujuan","quanyan","liuxiaoxiao","zhangyaping"]
for i in name_list:
    lst1=name_list.copy()
    lst1.remove(i)
    accept_person=random.choice(lst1)
    print(f"{i}送礼物给{accept_person}")

#2
d1={"a":1,"b":7,"c":5,"d":9}
d2={}
d2.update(d1)
for k1,v1 in d1.items():
    d2.pop(k1)
    for k2,v2 in d2.items():
        print(f"{k1}+{k2}的值为{v1+v2}")


#3
lst=[1,3,5,6,7,4,8,9]
lst_max=max(lst)
lst_min=min(lst)
print(f"列表中的最大值是{lst_max}")
print(f"列表中的最小值是{lst_min}")
sum=0
for i in lst:
    sum+=i
print(f"列表中数字的和为{sum}")
print(f"列表中数字的平均值为{(sum)/(len(lst))}")

#4
import os
doc=os.listdir()
for i in doc:
    print(i)